Methods of determining the thermal conductivity of building materials with high and medium thermal resistance
Authors:
- Henryk B. Łoziczonek,
- Marcin Furtak
Abstract
The subject of the analysis are methods of determining the thermal conductivity of building materials with high and medium thermal resistance. The thermal conductivity of building materials is determined by the thermal conductivity coefficient λ [W/mK]. There are a number of ways to determine the thermal conductivity λ. The coefficient λ may be determined under the steady state conditions or by the non-stationary (dynamic) method. The test conditions in the steady state conditions are defined by the standards ISO 8301, ISO 8302 and EN ISO 8497. Measurement of the coefficient λ [W/mK] in accordance with the PN-ISO 8301 standard is performed in a plate apparatus with heat flux sensors, while the measurement in accordance with PN-ISO 8302 is carried out with a plate apparatus with a guarded hot plate. The PN-EN ISO 8497 standard defines the test conditions with an apparatus with a guarded and calibrated hot pipe. Under steady-state conditions, the measurement of the coefficient λ is based on the one-dimensional Fourier's law applied to the one-dimensional temperature field. An alternative measurement technique is the non-stationary method, based on the measurement of thermal diffusivity. Thermal diffusivity is a specific material property that characterizes heat conduction in transient conditions. The phenomenon is used that in a certain time range the temperature change is a function of the natural logarithm of time. This value allows you to determine how quickly the material reacts to temperature changes. Thermal diffusivity is defined as the quotient of thermal conductivity and the product of specific heat and density. Alternative methods of determining the thermal conductivity coefficient λ have been developed in various research centers. This applies in particular to the measurement of the thermal conductivity of ultra-thin microsphere thermal insulation coatings. The value of the thermal conductivity coefficient λ obtained with this method for the microsphere thermal insulation coating was 0.001 [W/mK]. At the Małopolska Laboratorium Budownictwa Energoszczędnego (MLBE), the thermal conductivity coefficient λ [W/mK] is determined both under steady state conditions with a plate apparatus and the non-stationary method.
- Record ID
- CUTfdc83635b2d5426e8042120b1103e941
- Publication categories
- ; ;
- Author
- Other elements of collation
- fot.; rys.; Bibliografia (liczba pozycji) - 17; Oznaczenie streszczenia - Abstr.
- Substantive notes
- Tyt. źródła wg okł.
- Book
- Marschalko Marian, Marian Marschalko Yilmaz Işik, Işik Yilmaz Drusa Marian Marian Drusa (eds.): World Multidisciplinary Civil Engineering-Architecture-Urban Planning Symposium WMCAUS 2022, Prague, Czech Republic, 5-9 September 2022, AIP Conference Proceedings, no. 2928, 2023, [Maryland], American Institute of Physics, AIP Publishing, ISBN 978-0-7354-4663-2
- Keywords in English
- thermal diffusivity, heat transfer, thermal conductivity, heating, ventilation, air-conditioning, thermodynamic states and processes, transducers
- DOI
- DOI:10.1063/5.0171971 Opening in a new tab
- URL
- https://pubs.aip.org/aip/acp/article-abstract/2928/1/080025/2913222/Methods-of-determining-the-thermal-conductivity-of Opening in a new tab
- Language
- eng (en) English
- Score (nominal)
- 20
- Score source
- publisherList
- Score
- = 20.0, 12-03-2024, ChapterFromConference
- Additional fields
- Indeksowana w: Scopus
- Uniform Resource Identifier
- https://cris.pk.edu.pl/info/article/CUTfdc83635b2d5426e8042120b1103e941/
- URN
urn:pkr-prod:CUTfdc83635b2d5426e8042120b1103e941
* presented citation count is obtained through Internet information analysis, and it is close to the number calculated by the Publish or PerishOpening in a new tab system.